JP2001118532A - Cathode ray tube, method of assembling the same and method of measuring assembly accuracy - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To effectively prevent center axis deviation when assembling a cathode ray tube. SOLUTION: The cathode ray tube main body 2 and a cooling liquid holding body (coupler 5) filled with an internal space with a cooling liquid for cooling a front panel 22 of the cathode ray tube main body 2 are provided.
Two positioning reference portions (Xc1 and Xc2) on one of the long side and the short side of the front panel 22 and one location on the other side (Yc; not shown)
Is provided. At the time of assembling, a step of holding at least one of the cathode ray tube main body 2 and the coupler 5 using the outer surface portions (Xp, Xc1, etc.) whose distance from the central axis is known in advance as the respective alignment references, The method includes a step of abutting the cathode ray tube main body 2 and the coupler 5 while aligning the central axes based thereon, and a step of fixing the cathode ray tube main body 2 and the coupler 5 after the abutment.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a cathode ray tube used for a projector device for projecting an image on a screen and the like, and a method of assembling the same and a method of measuring assembly accuracy. Specifically, the present invention relates to an improvement in assembling accuracy in which the amount of deviation of the central axis between the cathode ray tube main body and the coolant holding body is reduced.

[0002]

2. Description of the Related Art In a projector device, an image projected on a front panel of a built-in cathode ray tube is enlarged by a projection lens and projected on a screen in front of the device. The cathode ray tube is R,
The three projected images are used for each of G and B, and the projected images are superimposed on a screen and displayed as a color image. Since a projection type cathode ray tube has a screen that is multiplied many times in a projector device, in order to secure a necessary brightness on the screen, for example, about three times higher brightness is required as compared with a direct view type. You. Therefore, the front panel of the projection type cathode ray tube is irradiated with a strong electron beam from a high-brightness electron gun and is heated to a high temperature, causing so-called burn-in, and the optical characteristics of the phosphor provided on the inner surface of the front panel and the durability of the device. It is easy to cause the deterioration of the property.

Therefore, a projection type cathode ray tube usually has a mechanism for cooling a front panel of the cathode ray tube main body. That is, a frame (coolant holding body) that covers the outer surface of the panel is provided so as to form an internal space facing the front panel of the cathode ray tube body, and the internal space is filled with the cooling liquid. As the cooling liquid, an ethylene glycol-based liquid having the same refractive index as the glass of the front panel is used. When the front panel is heated by the electron gun, the viscosity of the cooling liquid changes, and a temperature difference occurs. The change in the viscosity and the temperature causes the coolant to generate natural convection, thereby making the temperature of the front panel uniform and functioning as a medium for transmitting heat to the coolant holder formed by, for example, an aluminum die casting method. Is used as a heat sink for heat radiation.

On the other hand, the final lens of the projection optical system may be arranged on the surface of the coolant holder opposite to the front panel side, and in this case, the remaining lens group is mounted outside the final lens. This final lens is a spherical lens whose center is depressed toward the front panel, and if the mounting accuracy of the lens with respect to the cathode ray tube main body is poor, a focus shift of a projected image occurs. Normally, since the dimensional accuracy of the lens itself is high, the assembling accuracy of the final lens and the coolant holding member does not vary much. Therefore, it is important to improve the assembly accuracy of the cooling liquid holder and the cathode ray tube main body in order to increase the mounting accuracy of the lens to the cathode ray tube main body. Also, in recent cathode ray tube bodies, the front panel has a shape bulging inward toward the center in order to reduce the depth and reduce the size, and in this case, in order to prevent a focus shift from occurring, It is necessary to assemble the cathode ray tube body and the coolant holder with higher accuracy.

Under such a background, for example, Japanese Patent Application Laid-Open
JP-A-134946 discloses a method of assembling a cathode-ray tube and a method of measuring assembly accuracy in which the tube axis of a cathode-ray tube main body and the center axis of a lens can be aligned. FIG. 14 is a diagram for explaining a method of assembling a cathode ray tube described in this publication. FIG. 15 is a view for explaining a method of measuring the assembling accuracy of a cathode ray tube described in this publication.

In the method of assembling a cathode ray tube shown in FIG. 14, a positioning hole 101 formed in a table 100 in advance is used.
Positioning boss 111 of coupler (coolant holder) 110
With the adhesive 122 interposed between the front panel 121 of the cathode ray tube main body 120 and the coupler 110, and aligned from the tip of the abutting portion 102 extending vertically from one end of the table 100. The positioning is performed by abutting the reference pin 103 against the cathode ray tube main body 120. Further, the positioning in the z-axis direction is performed by abutting three z-direction positioning pins 104 projecting from the table 100 by a predetermined amount against the surface of the front panel. Thereafter, the adhesive 122 is cured to fix the cathode ray tube main body 120 and the coupler 110 together.

In this method of assembling the cathode ray tube, the positioning boss 111 on the coupler side is used as a positioning reference when the optical system lens is mounted later. 10
If the amount of projection of the positioning reference pin 103 which abuts on the side surface of the cathode ray tube main body 120 in the lateral direction from 2 is optimized in advance, then the center axis of the projection lens group attached to the coupler 110 is adjusted to the center of the cathode ray tube main body 120. Can be matched to the tube axis.

In the method of measuring the assembling accuracy of the cathode ray tube main body shown in FIG.
An XY table 132 is provided via the
Table 1 on the Y table 132 via the turntable 133
00 is provided. From the table 100, a z-direction positioning pin 104 projects upward. And
An abutting portion 134 extending in the vertical direction is formed at one end of the base 130, an alignment reference pin 135 is provided at the tip of the abutting portion 134, and an abutting pin 136 serving as a measurement gauge is provided at the base.
Is provided.

At the time of measurement, first, a position and a rotation angle of the table 100 are initially set using a master gauge accurately formed as a calibration reference of the measuring apparatus. The master gauge has the same outer shape as that when the coupler 110 and the cathode ray tube main body 120 are accurately aligned and assembled. First, the master gauge is set so that the positioning boss portion falls into the positioning hole 101 of the table 100. Then, XY
The scale of the measuring gauge 136 is reset after adjusting the table 132, the z-direction positioning pin 104, and the turntable 133, moving the master gauge so that the tip of the positioning reference pin 135 contacts a predetermined location of the master gauge. I do. As a result, the tube axis of the cathode ray tube and the center axis of the turntable 133 of the measuring device coincide. After the calibration, instead of the master gauge, the assembled coupler 110 and the cathode ray tube main body 120, which are the measurement objects, are similarly set, and the tip of the positioning reference pin 135 similarly contacts a predetermined position of the cathode ray tube main body 120. Is moved in the three-dimensional space while adjusting the rotation angle as described above. Measurement gauge 1 after this movement
By reading the scale of 36, the amount of displacement at the time of assembly can be measured.

[0010]

However, in this conventional method of assembling and measuring a cathode ray tube, the coupler 1
Due to the play between the ten positioning bosses 111 and the positioning holes 101 provided in the table 100, there is a disadvantage that the accuracy of assembly and measurement is poor. That is, the coupler 11
0 is usually formed by using a mold, so that a protruding portion such as the positioning boss 111 has a draft for improving the separation of the formed resin surface from the mold. Play is inevitably generated between the hole 101 on the table 100 side. Therefore, during assembly or measurement, the assembly of the coupler 110 and the cathode ray tube main body 120 may be displaced laterally with respect to the table 100 by a force of a pressing pin or the like. Due to this positional deviation, a center axis shift occurs in the assembly composed of the coupler 110 and the cathode ray tube main body 120, and a disadvantage that the measurement error increases due to an axis deviation between the assembly and the measurement stage portion occurs.

[0011] It is an object of the present invention to provide a cathode ray tube in which such a cathode ray tube is effectively prevented from being displaced in its central axis, a method of assembling the same, and a measuring method capable of increasing the measurement accuracy when measuring an assembly error. Is to provide.

[0012]

A cathode ray tube according to the present invention comprises a cathode ray tube main body and a cooling liquid attached to the cathode ray tube main body and cooling a front panel of the cathode ray tube main body heated by an electron beam from an electron gun. Is a cathode ray tube having a cooling liquid holder filled in an internal space facing the front panel, wherein the outer surface of the cooling liquid holder has a distance from a central axis parallel to a tube axis of the cathode ray tube. An alignment reference portion that is formed more accurately than the peripheral portion is provided. Preferably, the positioning reference portion is provided at two places on one side of the long side and the short side of the front panel and at one place on the other side.

The method for assembling a cathode ray tube according to the present invention comprises:
The cathode ray tube includes a step of fixing a coolant holding body filled with a coolant for cooling a front panel of the cathode ray tube body heated by an electron beam from an electron gun to an interior space facing the front panel to the cathode ray tube body. An assembling method, a step of holding at least one of the cathode ray tube main body and the cooling liquid holding body with an outer surface portion whose distance from the central axis is known in advance as a positioning reference, and the cathode ray tube main body and A step of abutting the coolant holders and, if necessary, adjusting a relative position based on the alignment reference; and a step of fixing the cathode ray tube main body and the coolant holder.

Preferably, in the step of holding at least one of the cathode ray tube main body and the coolant holding member, the cathode ray tube main body or the coolant is maintained until the outer surface portion is pressed against a positioning reference pin and does not move. Press the holder from the other side.

In the cathode ray tube having such a structure, not only the cathode ray tube main body but also the coolant holding member side is provided with an outer surface portion whose position from the central axis is accurately positioned, that is, a positioning reference portion. I have. When assembling the cathode ray tube, first, the cathode ray tube main body, the coolant holder, or both of the alignment reference portions are held. Specifically, until the positioning reference portion contacts the positioning reference pin,
Push from the other side to position and pride. After one or both of the cathode ray tube main body and the coolant holding body are brought close to each other and then butted together, the relative position is finely adjusted if necessary. After that, both are fixed by, for example, a leaf spring or an ultraviolet curable resin. For this reason, the assembling accuracy of the cathode ray tube main body and the coolant holder is mainly determined by the relative positioning accuracy of an assembling jig holding the positioning reference portion, for example, the resolution of a stepping motor. The accuracy of this mechanical alignment mechanism is typically orders of magnitude smaller than the play of mechanical parts having draft angles.

In the method for measuring the assembling accuracy of a cathode ray tube according to the present invention, a cooling liquid for cooling a panel surface of a cathode ray tube main body heated by an electron beam from an electron gun is filled in an internal space facing the front panel. A method for measuring the assembling accuracy of the assembled cathode ray tube in which the cooling liquid holding member is fixed to the cathode ray tube main body, and after fixing a predetermined position of the cathode ray tube main body, the tube axis of the cathode ray tube main body and The measurement gauge is pressed against the outer surface portion of the cooling liquid holding body whose distance from the parallel central axis is formed more accurately than the peripheral portion, and the distance of the outer surface portion from the tube axis of the cathode ray tube main body is determined. Measure.

Another method of measuring the assembling accuracy of a cathode ray tube according to the present invention is as follows. A cooling liquid for cooling a panel surface of a cathode ray tube body heated by an electron beam from an electron gun fills an internal space facing the front panel. A method for measuring the assembling accuracy of an assembled cathode ray tube in which a cooling liquid holder to be fixed is fixed to a cathode ray tube main body, wherein the cooling liquid holder is positioned at a center parallel to a tube axis of the cathode ray tube main body. After fixing at the outer surface portion where the distance from the axis is more accurately formed than the peripheral portion, pressing a measurement gauge against a predetermined portion of the cathode ray tube main body, the predetermined portion, from the central axis of the coolant holder. Measure the distance.

In any of the above-described methods for measuring the accuracy of assembling the cathode ray tube, in any of the above cases, the positioning of the cathode ray tube main body and one side of the cooling liquid holder with respect to the assembly of the cathode ray tube main body and the cooling liquid holder is performed. A portion (external surface portion or a predetermined portion) formed with high precision as a reference is held, and a measurement gauge is applied to the other high precision formed portion. At this time, it is known in advance that what value (reference value) the scale of the measurement gauge indicates in an ideal assembly when the holding portion of one of the high precision forming portions is set as the measurement origin. . Therefore, an assembling error can be determined from the difference between the indicated value of the scale of the actual measurement gauge and the reference value and the magnitude relation.

[0019]

FIG. 1 is a sectional view showing a structure of a projection type cathode ray tube according to an embodiment of the present invention as viewed from a side. FIG. 2 is a side view and a front view of the cathode ray tube main body, and FIG.
FIG. 4 is a side view and a front view of a cooling liquid holder (coupler), and FIG. 4 is a perspective view when the cathode ray tube main body and the coupler are assembled.

As shown in FIG. 1, the projection type cathode ray tube 1 is roughly divided into a cathode ray tube main body 2, an electron gun 3 built in the cathode ray tube main body 2, and a deflection mounted on the body of the cathode ray tube main body 2. It comprises a yoke 4, a coolant holder (coupler) 5 attached to the front panel side of the cathode ray tube main body 2, and a projection optical system 6 detachably mounted on the front surface of the coupler 5.

As shown in FIG. 2A, the cathode ray tube main body 2 has a trumpet-shaped glass tube 21 called a funnel, and a rectangular box-shaped glass 2 called a front panel, one of which is open.
2, and a plurality of glass parts such as the neck tube 23 are welded and assembled. Funnel 21
Although not shown, a phosphor layer, a cathode electrode, a magnetic shield component, and the like are appropriately disposed in the front panel 22, and the electron gun 3 is built in the neck tube 23. After the terminals of the electron gun 3 are drawn out and the inside of the cathode ray tube is evacuated, the end face of the neck tube 23 is closed. In the middle of the side surface of the funnel 21, holding surfaces 21a substantially parallel to the panel surface are formed at four diagonal points.

The front surface of the front panel 22 has a flat outer surface, whereas the inner surface rises inward toward the center and is curved, and a phosphor layer (not shown) is adhered to the inner surface. A plurality of positioning reference portions are provided on the outer surface of the peripheral wall of the front panel 22. Here, the positioning reference portion refers to a portion whose exact position is known in advance with respect to a reference axis (tube axis, center axis), or formed with higher positional accuracy than the surrounding portions. Specifically, in this example, as shown in FIG. 2, an alignment reference portion Xp in the x direction is provided on the outer peripheral surface of the panel in the short side direction of the panel. Direction alignment reference portions Yp1 and Yp2 are provided. These alignment reference portions may not be apparently distinguishable if the exact position is simply known in advance, but the positional accuracy is higher than the surroundings by polishing or the like, or formed to be identifiable by marking or the like. Is more preferable.

As shown in FIGS. 3 and 4, the coupler 5 has a plate frame 51, and a substantially square panel-side opening 51a, which is slightly smaller than the front panel 22, is formed substantially at the center of the plate frame 51. ing. The coupler 5 includes a substantially rectangular box-shaped liquid tank 52 protruding forward from the periphery of the panel-side opening 51a, and a leaf spring support protruding rearward in parallel with the long side of the panel-side opening 51a. 56. The liquid tank section 52 has a volume necessary to store a predetermined amount of cooling liquid. On the front surface of the liquid tank portion 52 facing the panel side opening portion 51a, a substantially circular lens mounting opening 5 is provided over almost the entire surface.
2a is provided. In the lens mounting opening 52a,
As shown in FIG. 1, a spherical lens 6a which is the final lens of the projection lens system 6 is dropped through an O-ring 58,
The edge of the spherical lens 6a is held down and fixed by the plate 7 screwed to the front surface of the liquid tank 52. On the front surface of the liquid tank around the lens mounting opening 52a, two positioning bosses 53 for positioning the cylindrical frame holding the other projection lens group 6b are provided on both sides in the diagonal direction so as to protrude forward. ing.

In one of the other diagonal directions, there is provided an opening 54 for a pressure regulating valve called a bellofram. The opening 54 is connected to the internal space of the liquid tank 52 via the communication hole 54a. The bellofram is screwed so as to close the opening 54. Velofram is made of an easily deformable film made of, for example, ethylene propylene rubber, a compounded material of ethylene propylene rubber and silicon, or butyl rubber, and the volume of the cooling liquid changes according to the liquid temperature from the state at the time of filling the cooling liquid. It absorbs the change and swells outside or indents outside the coupler 5. Thus, regardless of the volume change of the coolant, the pressure is kept substantially constant, and the liquid leakage due to the thermal expansion of the coolant and the damage of the coolant holding component are effectively prevented.

In addition to the opening 54, a cooling liquid inlet 55 is opened on the peripheral wall of the liquid tank 52. Although not particularly shown, a screw is attached to the inlet 55 via an O-ring as a stopper so that the coolant does not leak from the inlet 55 to the outside.

In the coupler 5 having the above-described structure according to the present embodiment, a plurality of positioning reference portions are provided on the outer peripheral surface of the liquid tank portion 52. Specifically, in this example,
As shown in FIG. 3, two x-direction alignment reference portions Xc1 and Xc2 are provided on the outer peripheral surface in the panel short side direction at a distance from each other, and y is provided on the outer peripheral surface in the panel long side direction.
A direction alignment reference portion Yc is provided. In these alignment reference portions, the position accuracy from the center axis of the coupler is higher than that of the surroundings by a method such as locally forming the mold to form the coupler 5 or performing local polishing after forming. . In addition, although not essential, it is more preferable to have a feature on the outer shape or to be identifiable by marking or the like.

On the other hand, a positioning boss 56a for a leaf spring for attaching the coupler 5 to the cathode ray tube main body 2 is provided on a distal end surface of a leaf spring supporting portion 56 erected on the back side of the plate frame 51.
Are provided in pairs. The distal end surface of the leaf spring 8 attached to the leaf spring support portion 56 comes into surface contact with the holding surface 21a provided on the funnel 21 in FIG. 2, and the cathode ray tube main body 2 is moved to the panel side of the coupler 5 by the elastic force of the leaf spring. It is pressed so as to close the opening 51a. An O-ring 57 is interposed in a circumferential groove around the panel-side opening 51a, thereby preventing liquid leakage at a contact portion between the cathode ray tube main body 2 and the coupler 5.

The interior space of the coupler 5 formed by completely sealing the front and back sides in this way is filled with a cooling liquid. As the cooling liquid, for example, a mixed liquid of ethylene glycol and glycerin is used. This mixture
When the front panel 22 is heated by the high-brightness electron beam from the electron gun during use, the viscosity of the liquid changes and a temperature difference occurs. The change in the viscosity and the temperature causes the natural convection of the cooling liquid, thereby making the temperature of the front panel 22 uniform and functioning as a medium for transmitting heat to the entire coupler 5.
Thus, heat is radiated using the coupler 5 which is an aluminum die-cast product as a heat sink. Since the image is projected to the outside through the cooling liquid, the material of the cooling liquid is selected so that the refractive index of the cooling liquid is almost the same as the refractive index of the glass and the brightness does not decrease due to interface reflection. You.

Next, the details of the procedure for assembling the cathode ray tube main body and the coupler will be described together with the main configuration of the assembling apparatus. 5 to 12 are cross-sectional views along the x direction during the assembly of the cathode ray tube main body and the coupler.

As shown in FIG. 5, for example, the coupler 5 is set on an assembly jig. The assembling jig 60 includes a base 61, an x-direction positioning reference pin 62 and a pressing pin 63 for holding a coupler held movably in the x direction with respect to the base 61, and an x direction and a z direction with respect to the base 61. X for holding the cathode ray tube body movably held in
Direction alignment reference pin 64 and pressing pin 65
And three z-direction positioning pins 66. A through hole 61a penetrating the front and back surfaces is formed in the center of the base 61, and a z-direction positioning pin 66 is passed through the through hole 61a. Further, two boss holes 61b are formed on the base surface around the through holes. Note that the assembling jig 60 is also similar to the y direction in the same manner as the x direction.
A positioning reference pin 67 for the coupler, a positioning reference pin 68 for the cathode ray tube main body (FIG. 4), and a pressing mechanism are provided.

When fixing the coupler 5, first, the coupler 5 is placed on the base 61 so that the positioning boss 53 falls into the boss hole 61b. x direction alignment reference pin 6
2 is set to a predetermined value, and the coupler 5 is pressed by the pressing pin 63 from the opposite side. At this time, x
The tip of the direction alignment reference pin 62 abuts on the x direction alignment reference portion Xc1 or Xc2, and the coupler 5 is held by the x direction alignment reference pin 62 and the pressing pin 63. Thereby, as shown in FIG. 6, the coupler 5 is held in a state where it is accurately positioned on the assembly jig 60.

Next, three z-direction positioning pins 66
(A projecting amount in the z direction) is set to a predetermined projecting state.
Further, the protrusion amount of the x-direction alignment reference pin 64 is set to a predetermined value. The heights of the x-direction positioning reference pin 64 and the pressing pin 65 are adjusted according to the set height of the z-direction positioning pin 66. Before or after this pin adjustment, the O-ring 57 is set in a groove provided around the panel-side opening 51a of the coupler 5, as shown in FIG. Then, the three z-direction alignment pins 6 after the adjustment
After the cathode ray tube main body 2 is placed downward so that the center portion of the panel surface is in contact with the cathode ray tube main body 6, the cathode ray tube main body 2 is pressed by a pressing pin 65 opposite to the x-direction positioning reference pin 64. At this time, the tip of the x-direction positioning reference pin 64 abuts on the x-direction positioning reference portion Xp, and the cathode ray tube main body 2 is held by the x-direction positioning reference pin 64 and the pressing pin 63. Thereby, as shown in FIG.
The cathode ray tube main body 2 is held in a state where it is accurately positioned on the assembly jig.

While the cathode ray tube main body 2 is held by the x-direction positioning reference pin 64 and the pressing pin 63, the z-direction positioning pin 66 is slowly lowered by an elevating mechanism (not shown), as shown in FIG. The panel surface of the main body 2 is brought into contact with the plate frame surface of the coupler 5. At this time, since the fixing of the coupler 5 or the cathode ray tube main body 2 to the assembling jig has already been performed with high precision as described above, the coupler 5 can be accurately butted against the cathode ray tube main body 2.

After this matching, as shown in FIG.
The leaf spring 8 is screwed to the distal end of the leaf spring supporting portion 56 of the coupler 5 with the other end of the leaf spring 8 abutting the funnel holding surface 21a. Thus, the coupler 5 and the cathode ray tube main body 2 are fixed by the elastic force of the leaf spring 8.

As shown in FIG. 11, the spherical lens 6 is inserted into the lens mounting opening 52a of the coupler 5 via an O-ring 58.
After inserting a, the plate 7 is screwed from the outside. Then, as shown in FIG.
2, 63, 64, 65 are retracted, and the assembly of the cathode ray tube main body 2 and the coupler 5 is removed from the jig.

In the cathode ray tube and the method of assembling the same according to the present embodiment, the coupler 5 is fixed to the jig 60 by using the positioning reference portions Xc1, Xc2 and Yc which are accurately positioned with respect to the center axis. In addition, the positioning reference portions Xp and Yp, which are accurately positioned with respect to the tube axis.
The cathode ray tube main body 2 is fixed to the jig 60 using 1 and Yp2, and then the cathode ray tube main body 2 and the coupler 5 are butted and fixed. Therefore, accurate assembling is possible without mechanical backlash, thereby greatly reducing optical defocus. Further, the assembling device also has a relatively simple structure.

FIG. 13 is a diagram showing a method of measuring assembly accuracy. The apparatus used for measuring the assembly accuracy includes a measurement head 70 that can move in three axes, and a measurement gauge 71 whose projection amount from the tip of the measurement head 70 is variable. The measurement of the assembly accuracy is performed, for example, in a state where the x-direction positioning reference pin 62 and the push-out pin 63 on the coupler side are removed. First, the measurement head 70 is moved to an initial position where the relative position is known with respect to the alignment reference portions Xp, Yp1, and Yp2 on the cathode ray tube main body 2 side. The protruding amount of the measuring gauge when it collides with a measurement point (for example, the x direction alignment reference portion Xc1) is detected. Similarly, the positions of the other second and third measurement points Xc2 and Yc with respect to the cathode ray tube main body 2 are measured. From the three measurement data, the assembly displacement amount and the displacement direction of the coupler 5 with respect to the cathode ray tube main body 2 are calculated.

In the method for measuring the assembling accuracy of the cathode ray tube according to the present embodiment, the assembling accuracy of the cathode ray tube main body 2 and the coupler 5 can be accurately measured with almost no mechanical play. In addition, since the configuration of the measurement device is simple and does not take much time, the measurement cost can be reduced. In addition to this measurement method, in addition to the accuracy measurement immediately after assembly, an impact drop test,
It can be applied to measurement of displacement between panel and coupler after vibration test.

In the above-described embodiment of the present invention, various modifications are possible. For example, the position and number of the alignment reference portions of the cathode ray tube 1 are not limited. However, for accurate positioning, usually, at least three alignment reference parts are required, one on each side of the cathode ray tube main body 2 and the coupler 5 and two on the other orthogonal side. Cathode ray tube body 2
And the structure of the coupler 5, its mounting method, assembling device (assembly jig 60) and measuring device (measuring head 7)
The structure of the zero and the measurement gauge 71) is not limited to the illustrated one. Further, when the cathode ray tube main body 2 and the coupler 5 are abutted with each other, the cathode ray tube main body 2 can be brought close to each other while holding the cathode ray tube main body 2 with a pin. Alignment reference part X
The positions of p, Yp1 and Yp2 may be measured.

[0040]

According to the cathode ray tube and the method of assembling the same according to the present invention, both the cathode ray tube main body and the coolant holding member are held by the assembling jig while being positioned at the high precision forming portion (alignment reference portion). After that, they are fixed by abutting each other. Therefore, as compared with a conventional holding method in which a projection such as a boss having a draft angle is dropped into the hole of the jig, the assembling accuracy is improved by the higher fixing accuracy of the jig.

In the method for measuring the assembling accuracy of a cathode ray tube according to the present invention, the cathode ray tube main body and one side of the coolant holding member are accurately and reliably held, so that even if a force is applied during the measurement, the object is to be measured. The assembly of the cathode ray tube main body and the coolant holder does not shift. Therefore, the measurement accuracy can be maintained at all times. In addition, it is only necessary to apply a measurement gauge to the other side while holding the cathode ray tube main body and one side of the cooling liquid holder, so that the measuring method is simple and calibration reference adjustment is unnecessary. For this reason, the structure of the measuring device can be simplified, and the time and cost required for the measurement can be saved.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a structure as viewed from a side surface of a projection type cathode ray tube according to an embodiment.

FIG. 2 is a side view and a front view of a cathode ray tube main body according to the embodiment.

FIG. 3 is a side view and a front view of a cooling liquid holder (coupler) according to the embodiment.

FIG. 4 is a perspective view when assembling the cathode ray tube body and the coupler according to the embodiment.

FIG. 5 is a cross-sectional view along the x direction when the coupler according to the embodiment is fixed to an assembly jig.

FIG. 6 is a cross-sectional view after holding the coupler, following FIG. 5;

FIG. 7 is a sectional view following FIG. 6 when the cathode ray tube main body is supplied to an assembling jig;

FIG. 8 is a sectional view following FIG. 7 after the cathode ray tube main body is supplied.

FIG. 9 is a cross-sectional view following FIG. 8 after the cathode ray tube main body has been butted against the coupler.

FIG. 10 is a cross-sectional view after attachment of the leaf spring, following FIG. 9;

FIG. 11 is a sectional view following FIG. 10 when a spherical lens is attached.

FIG. 12 is a sectional view following FIG. 11 when the assembly of the cathode ray tube main body and the coupler is taken out from the jig.

FIG. 13 is a diagram illustrating a method of measuring assembly accuracy according to the embodiment.

FIG. 14 is a view for explaining a method of assembling a conventional cathode ray tube.

FIG. 15 is a diagram illustrating a method for measuring the assembly accuracy of a conventional cathode ray tube.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Cathode tube, 2 ... Cathode body, 21 ... Funnel,
21a: holding surface, 22: front panel, 23: neck tube, 3
... Electron gun, 4 ... Deflection yoke, 5 ... Coupler (coolant holder), 51 ... Plate frame, 51a ... Panel side opening, 5
2 ... liquid tank part, 52a ... lens mounting opening, 53 ... lens positioning boss, 54 ... velofram opening, 54
a: communication hole, 55: injection port, 56: leaf spring support, 56
a: positioning boss of leaf spring, 57, 58: O-ring, 6
... Projection optical system, 6a spherical lens, 6b other projection lens group, 7 plate, 8 leaf spring, 60 assembly jig, 61 base, 61a through hole, 61b boss hole,
62, 64, 66, 67, 68 ... alignment reference pins,
63, 65: pressing pin, 70: measuring head, 71:
Measurement gauges, Xc1, Xc2, Xp... X-direction positioning reference portion, Yc, Yp1, Xp2.

Claims (10)

[Claims] A cooling liquid for cooling a front panel of a cathode ray tube main body and a cathode ray tube main body attached to the cathode ray tube main body and heated by an electron beam from an electron gun is filled in an internal space facing the front panel. A cathode ray tube having a cooling liquid holder, wherein a distance from a center axis parallel to a tube axis of the cathode ray tube is formed more accurately on an outer surface of the coolant holder than a peripheral portion. A cathode ray tube provided with a section. 2. The cathode ray tube according to claim 1, wherein the positioning reference portion is provided at two positions on one side of the long side and the short side of the front panel and at one position on the other side. 3. A step of fixing a cooling liquid holding body filled with a cooling liquid for cooling a front panel of the cathode ray tube main body heated by an electron beam from an electron gun into an internal space facing the front panel to the cathode ray tube main body. A method of assembling a cathode ray tube comprising: a step of holding at least one of the cathode ray tube main body and the cooling liquid holding body with an outer surface portion whose distance from a central axis is known in advance as a reference for each alignment, A step of abutting the cathode ray tube body and the coolant holder and, if necessary, adjusting a relative position based on the alignment reference; and fixing the cathode ray tube body and the coolant holder. How to assemble a cathode ray tube. 4. In the step of holding at least one of the cathode ray tube main body and the cooling liquid holding body, the cathode ray tube main body or the cooling liquid holding liquid is held until the outer surface portion is pressed against an alignment reference pin and does not move. The method for assembling a cathode ray tube according to claim 3, wherein the body is pushed from the opposite side. 5. The method of assembling a cathode ray tube according to claim 3, wherein an outer surface portion of the cooling liquid holding member is formed more accurately at a distance from the central axis than at a peripheral portion. 6. An outer surface portion serving as an alignment reference includes two portions on one of a long side and a short side of the front panel in the cathode ray tube main body and the cooling liquid holder, respectively.
4. The method for assembling a cathode ray tube according to claim 3, wherein the cathode ray tube is provided at one position on the other side. 7. A cooling liquid holder filled with a cooling liquid for cooling a panel surface of the cathode ray tube main body heated by an electron beam from an electron gun in the internal space facing the front panel is fixed to the cathode ray tube main body. A method for measuring the assembling accuracy of a cathode ray tube after assembly, wherein after fixing a predetermined position of the cathode ray tube main body, a distance from a central axis parallel to a tube axis of the cathode ray tube main body is longer than a peripheral portion. A method for measuring the assembling accuracy of a cathode ray tube, wherein a measuring gauge is pressed against an accurately formed outer surface portion of the cooling liquid holder, and a distance of the outer surface portion from the tube axis of the cathode ray tube main body is measured. 8. A cooling liquid holder filled with a cooling liquid for cooling a panel surface of the cathode ray tube main body heated by an electron beam from an electron gun in the internal space facing the front panel is fixed to the cathode ray tube main body. A method for measuring the assembling accuracy of a cathode ray tube after assembling, wherein a distance from a center axis parallel to a tube axis of the cathode ray tube main body is formed more accurately than a peripheral portion of the cooling liquid holder. A method for measuring the assembling accuracy of a cathode ray tube, wherein a fixing gauge is pressed against a predetermined portion of the cathode ray tube main body after fixing at an outer surface portion, and a distance of the predetermined portion from a center axis of the coolant holder is measured. 9. The cathode ray tube main body and an outer surface portion which is a fixing place or a measurement place of the cooling liquid holder are one of a long side and a short side of the front panel in the cathode ray tube main body and the cooling liquid holder, respectively. The method for measuring the assembling accuracy of a cathode ray tube according to claim 7, wherein the assembly is provided at two places on one side and one place on the other side. 10. An outer surface portion, which is a fixing point or a measurement point of the cathode ray tube main body and the cooling liquid holding body, is one of a long side and a short side of the front panel in the cathode ray tube main body and the cooling liquid holding body, respectively. 9. The method for measuring the assembling accuracy of a cathode ray tube according to claim 8, wherein the cathode ray tube is provided at two places on one side and one place on the other side.